Elevator safety device



Dec. 9, 1 24- 1,518,902

N. s. DICKINSON ELEVATOR SAFETY DEVICE Filed June 18, 1920 Patented Dec. 9, 1924.

UNITED "STATES iPAT E NT FFIC E NEVILLE s. nrcxrnson, or GLEN RIDGE, NEW annsnr, sssrsnon T0 ELEVATOR sorrnrns COMPANY, me, a conronnrron on NEW JERSEY.

ELEVATOR SAFETY DEVICE.

Ap ca io le ha Tooll whom. it may concern:

Be it known that I, Nnvrnnn S. DroKrN- soN, a citizen of the United States, residing at Glen Ridge, New Jersey, have invented certain new and useful Improvements in l*levat,or Safety Devices, which the following is a clear, full, and exact description.

My invention relates to elevator safety appliances, and particularly appliances suit-- able for electrically controlled elevators, and an objectof theinvention is to provide a suitable arrangement of control whereby it will he impossible tostart. the elevator unless a certain order of manipulation of the control devices is followed. it is customary to close and latch the elevator gates or hatchway .doors, and then to manipulate thestarting' device. It may often-happenthata careless operative will manipulate the starting device before closing the gate at the hatchway at. thefioor at which the elevator may be. This is a dangerous procedure, and in'some States laws have heen passed requiring elevators to be equipped with devices whereby it is impossible to start the elevator until all hatchway gates are closed.

A further object of my invention is to pre vent theelevator moving under control of the starting device-if this device is manipulated prior to the. closing of the elevator gates, even though said gate or gates are sub sequently closed,.and until said starting device is again moved to neutral position.

A still further object of my inventionis to prov-idea safety appliance which is readily adaptable ,to elevator installations now in use, and particularly to elevators which are started under control otta hand rope.

Other objects and important features of the invention will become apparent from the following detailed I description, and claims when considered in connection with the accompanying drawings, in which I have shown my invention in diagrammatic form and as applied to rope-controlled elevator.

.lRei'erring to the drawings, 1 indicates a hand rope passing over a pulley 2 at the bottom otthe elevatorshaift and over a. pulley which maybe situated near the top thereof. is is usual in this type of elevator, the shaft 1 carrying the pulley 8 may also carry an electric controller for properly controlling the current supplied to the motor to start the same with the proper acceleration and 1820. Serial No. 330,0 l7.

to reverse the same. The particular construction of this controller forms no part of my present invention and may be of any suitable construction. I have therefore not shown the controller in detail, but in practice it is mounted on the shaft l and-controls an electric circuit 5 leading to the brush 6 of the motor '7. T he other brush 8 is in connection with a. wire 9 leading to a. contact 10 on a rheostat by which the starting of the motor is controlled. The rheostat may be of any suitable and well known construction, and in the diagram 1 have indicated an arm 11 pivoted at 12; and to the other end of said arm a wire 13 is connected. This wire leads to the controller and is connected thereto at i l. lVires l5 and 16 lead to the motor field 1'7. A solenoid 18, for cutting out resistance in the motor circuit and having wires 19 and 20, is also provided, which wires also lead to the controller. A dashpot 21 governs the movement of the solenoid core 22 so that the resistances in the rheostat are gradually cutout as the motor starts. A brake drum 23 provided, and this may be in connection v-rith the motor shaft by means the shaft 242. Brake shoes 25 bear upon the brake drumand are held thereagainst by the usual springs (not shown). A sole'noidQG connected to the toggle links 27 acts to re,- lease said brake shoes when the solenoid is ctuated.

The above described elevator control mechanism lo of well known construction, and it is in connection therewith that my impro'ements are adapted to be used with p a ic-ally nochange in the actual structure or the operating mechanism, and with but slight change in the wiring. In the construction now in use, the circuit to the solenoid. 26 is supplied through the controller and ordinarily, as soon as the elevator rope l is pulled, either in one direction or the other, the solenoid '26 is energized to release the brake shoes. In my improved construction, however, the means for actuating this solenoid forms an important feature of the invention, and the circuit through it is controlled in a novel manner, as will be pointed out later.

he controller is supplied with current by lead wires and 30 connected to a main teed wire 31 on one side of the line, and in the form of mechanism already in use, the

other supply wire 29 leading to the controller is connected directly to the other side of the circuit, and in operation, any pull upon the elevator rope 1 from normal position will cause the release of the brake shoes through energization of the solenoid 26 and the closing ofsuch contacts within the con troller as would cause the current to pass through the motor in a direction to cause the elevator to move up or down, depending upon whether the rope 1 waspulled upwardly or downwardly from normal position.

In my improved construction, however, the lead wire 29 does not go directly to the other side of the line, but instead, said circuitleads from 29 through the wire 32 to a contact 33 forming part of a switch 34, which switch is under the control of a line switch magnet 35; and when said line switch magnet is energized, its core 36 is pulled up, thereby bringing together the contacts and The elevator operating circuit then contin ues from 33 through 34 to thecontact 37, wire 38, wire 39, wire 40 to the other side of the line at 41, being connected at this point with the other main feed wire 42. .Vhenever the line switch magnet 35 is energized, the elevator operating circuit supplies current to the controller and the elevator motor may be started.

In order to control the energization of said line switch magnet and therefore control the elevator operating circuit, I provide a switch which is closed by moven'ient of the elevator rope in either direction. While various devices may be employed to accomplish this, in the particular embodiment of the inven tion illustrated, I have shown a ball 43 and a ball. 44, said balls being fixed to the elevator rope at suitable points, said balls being close together, and extending between them is an arm 45 fixed to a shaft 46, said shaft carrying a disc having an electric contact 47 extending through a considerable portion of its circumference. Said disc, however, has an insulated portion 48 upon which an electric contact 49 normally rests. A second electric contact 50 rests upon the metallic portion 47. A wire 51 is connected to the contact 50 and is connected through the wire 52 to the main feed wire 42, a fuse 53 being connected between the wires 52 and 42 at the points 54 and 55. The purpose and function of this fuse will be explained later. From the contact 49 a wire 56 is connected through the wire 57 to the line switch magnet 35, the circuit through said magnet including a wire 58, wire 59, contact 60, contact 61, wire 2, wire 63 which may be connected at 64 to the main feed wire 31. Suitable resistance 64 may be interposed in this circuit. Normally the circuit through the line switch magnet 35 is broken at 61 and also at 49. Under these conditions, movement of the elevator rope 1 in either direction will move the arm 45 and cause such rotation of the disc that its metallic contact 47 will engage the contact 49, while the contact 50 remains in electrical engagen'ient with 47. The circuit, however, through the line switch magnet remains broken at 6061, so that such movement of the elevator rope does not result in starting the elevator, as the operating circuit is still open at 324-3 The arm 45 above referred to is normally maintained in a neutral position by a spring 65 connected to some stationary part 66.

In addition to closing the circuit for the line switch magnet at the elevator starting contact device, actuated by the elevator rope, it is necessary to close the contact 6061, and this is brought about when the gate contacts are closed. These gate contacts are represented diagrammatically at 67, 68 and 69 and are in series, and when all of them are closed, current will flow from the main line wire 31 to wire 70, through resistances 71 and 72 to the wire 73, through contact 69 wire 74, contact 68 wire 75, contact 67 wire 76, wire 77, wire 78, wire 79, relay magnet 80, wire 81, wire 82, to the point 54 where it passes through the fuse 53 to the other feed wire 42. The relay magnet 80 is provided with a core 83, to which is connected a lever 84 pivoted at 85. The lever 84 is in the form of a bell crank, the other arm 86 of which carries at one end a member 87 to which is connected a switch 88. A spring 89 is connected to the bell crank 84 and normally acts to hold the switch 88 out of engagement with the cont-acts 60-61. When the gate contacts are all closed and the mag net 80 is energized, switch 88 closes contacts 60-61, and if at that time the elevator rope is actuated to close the elevator operating switch, current will flow through the line switch magnet 35 and this will pull up'its core 36 and cause the contacts 3337 to be bridged by the switch 34, thus permitting current to pass to the elevator operating circuit which is properly distributed by the electric controller already referred to to cause starting of the motor. The elevator will then move up or down according to the direction of pull on the rope 1.

Closing of the gate contacts and subsequent operation of the elevator starting switch is the normal operation. But in case the elevator starting switch is closed prior to the closing of all of the gate contacts, means are provided to prevent closing of the elevator operating circuit even though the gate contacts, or any of them, are subsequently closed.

The means for accomplishing this consist of a shunt circuit including said gate contacts and said elevator starting switch, but not including the relay magnet 80. The member 87 besides carrying the switch 88,

also carries a switch 90, bridging contacts 91 and 92 forming part of said shunt circuit, which circuit passesthrough thegatecontacts, through the. wires 77-7 8, 9l92-,

wire 98, wire 56 to the. elevator starting swltch and through this to wires 5l52 to 4 2 if said starting switch is closed. It results, therefore, that if said starting switch is closed prior to the closing of the gate con tacts, and said gate contacts are subsequentlyclosed, current will flow through said shunt circuit and the relay magnet 80 will notbe Thereforecontacts 6061 will i energized. remain open and the'line switch magnet 35 will not be energized. It will be noted that:

while .the current ispassingthrough said shunt circuit, there is-also a circuit formed through sa1d gate contacts and through wires77, 78, 7 9, relay magnet 80 and-wires fil -82 to the otherside of the-line, but the resistance of the relay magnet SOis such that this current is small and is not sufiicient to cause actuation of .the relay magnet, the greater portion of the current flowing through said shunt circuit. Current will continue to pass through said shunt circuit control the closing of the elevatoroperat-- ing circuit, but it also closes a circuit through the brake solenoid 26, and for this purpose the core 36 of the solenoid 35- 'carries a member 94 which, when thesolenoid 35. is energized, bridges the contacts 95 and 96 causing a circuit to be made which leads from the point 41 through wire 40, wire 39,

wire 38, contacts 9596, wire 97, wire 98,

wire 99, solenoid 26, wire 100 to the main feed wire 31 at the point 101. Energiza tion of the line switch magnet 35will, therefore, result in releasing the brake shoes 25.

The resistances 7172 and the fuse53, in cluded in the circuit through the gate contacts and through the relay 80, furnish a means for protecting the device against accidental grounds. If, for instance, any gate contact should be grounded with the main wire 81, the resistances 71 and 7 2 would be cut out, and a heavy current will pass through the fuse Under these circumstances, the fuse would be blown and the elevator operating circuit could not be closed. If, on the other hand, a ground occurred between the gate contacts, or any one of them, and the feed wire 42, no current would be supplied to the relay 80 and again the elevator operating circuit controlled by the line switch magnet would not be supplied with current.

In operation the gate contacts at 67, (38 and69. are first closed. and afterwards the rope 1 is pulled, resulting in the elevator motor being operated. Closing of the gate contacts establishes a circuitfrom the main feed wire 31, through the wire 70, resistances 71 and 72, wire 73,'gate contacts 67, 68 and current flows through wires 81 and 82 to the 'point lil and-across the fuse 53 to the point 55 on the other side of'the line. lriovement of this magnet breaks contact between :the terminals 91 and 92 and estab lishes contact between theterminals 60 and 61 so that current immediately flows from the =1nainfe'ed wire 31 throughresistance Gal wire 63,-wire 62, wire 59, wire 58, through the line magnet 35, whenceit flows through wire-57to contact 4-9 and contact 50 through wire 51 to the point o l, to the other side of" the line. Energizati-on of the line switch magnet 35 bridges the terminals 33, 37 thereby permitting current to flow from the point" 41 through the wire a0, wire 39 and wire 38, and terminals 37 and 33, to wire 32, wire 29 and through the controller which has been so positioned by the pull on-the rope l that current will flow through the motor 7 to cause the elevator to move in a. downward direction, the current passing out of the controller throu h the wires 28 and SO'back to the other side of the line at 31.

This is the normal manner in which the device-is intended to function. but if, for

any reason, the operative should actuate the rope 1 to put the terminals 49 and 50 into electrical contact before closing all of the gate contacts, then a shunt circuit will be established, as has been described, around the relay magnet 80 and not enough current would flow through said magnet to actuate it and therefore the contacts 60 and 61 will not he electrically connected and the line switch magnet 35 will therefore not be energizedynor the controller supplied with current. it will thus be seen that the"usual controll r for elevators in systems now installed is placed under control ofthe line switch magnet 85 of my present improvement and this magnet in turn is under control of the relay magnet 80 which in turn is controlled by the gate contacts.

It will also be seen that the brakes normally holding the motor stationary are released under control of the line switch magnet 35 so that unless this magnet is energized, not only is no current supplied to the motor, but no current is supplied to the brake release solenoid 26.

lVhile I have shown and described one practical improvement of my invention, it is obvious that variations may be resorted to without departing from the spirit thereof, and parts of the device may be used without others.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. In an elevator safety appliance, the combination with an elevator operating circuit, of means controlling the closing of said circuit, said means including a relay magnet and gate contacts in series therewith and also including an elevator starting switch, and means preventing the closing of said operating circuit if said elevator switch is closed prior to said gate contacts, said preventing means including a shunt circuit around said relay magnet, said shunt circuit including said elevator starting switch.

2. In an elevator safety appliance, the combination with an elevator operating circuit, and a line switch magnet for closing said circuit, of a relay magnet, gate contacts in series for closing a circuit through said relay magnet, a switch in circuit leading to said line switch magnet, whirh circuit is closed on actuation of said relay magnet, and an elevator starting switch also in said line switch magnet circuit.

3. In an elevator safety appliance, the combination with an elevator operating circuit, an elevator starting switch and gate contacts, of a line switch magnet for closing said elevator operatingcircuit, a control circuit including a relay magnet in series with said gate contacts, a switch in the circuit with said line switch magnet which is closed by said relay magnet on actuation thereof, a second switch normally closed but which is opened by said relay magnet on actuation thereof, said elevator starting switch and said gate contacts being in circuit with said second switch, said circuit having less resistance than said control circuit, whereby if said elevator switch is closed before said gate contacts, current will flow through said second switch and said relay magnet will not be actuated.

4. In an elevator safety appliance for rope-controlled elevators, the combination with an elevator motor, an electric controller therefor, and a rope operating on said controller, of a line circuit for said controller, a switch closed by movement of said rope in either direction, and means including gate contacts for rendering said switch effective to cause current to be supplied to said electric controller only in case said gate contacts are first closed.

5. In an elevator safety appliance for rope-controlled elevators, the combination with an elevator motor, an electric controller therefor, and a rope operating on said controller, of a line circuit for said controller, a switch closed by movement of said rope in either direction, and means including gate contacts for preventing said switch from causing current to be supplied to said electric controller unless all of said gate contents are first closed.

6. In an elevator safety appliance for rope-controlled elevators, the combination with an elevator motor, an electric controller therefor, and a rope operating on said c011- troller, of a line circuit for said controller, a line switch magnet for closing said circuit, a switch closed by movement of said rope in either direction, said switch being in the circuit of said line switch magnet, a relay magnet, gate contacts for closing a circuit through said relay and magnet, and a switch in said line switch magnet circuit closed by said relay magnet.

7 In an elevator safety appliance for rope-controlled elevators, the combination with an elevator motor, an electric controller therefor, and a rope operating on said controller, of a line circuit for said controller, a line switch magnet for closing said ClI cuit, a switch closed by movement of said rope in either direction, said switch being in the circuit of said line switch magnet, a relay magnet, gate contacts for closing a circuit through said relay magnet, and means preventing closing of said elevator operating circuit if said rope-actuated switch is closed prior to said gate contacts, said preventing means including a shunt circuit around said relay magnet, said shunt circuit including said rope-actuated switch.

Signed at New York city, New York, this 10th day of June 1920.

NEVILLE S. DICKINSON. 

